I think UABuckeye meant subjectively questioning the ceiling of the offense.
And I think you, like a lot of people, have assumed his arm strength is less than adequate because the other guy known as 12-Gauge had a cannon for an arm. JT's arm strength is not limited, nor does it impact what OSU wants to do on offense.
Even if a QB has a weak arm, they can still be successful in college. Just look at what the BGSU QB did this year. It takes a good half-hour for the ball to get there on a 5 yd out but he still gets it done.